26 October 2018
It’s been a very Billy-Goaty week for me. Three times since Sunday afternoon, I’ve taken people to the Billy Goat Trail’s “A” loop in C&O Canal National Historical Park. On Tuesday and Thursday, it was my NOVA Physical Geology students. On Sunday, though, it was just my son and me.
Good news! He helped me discover a new fold by exploring some new rock outcrops and climbing on them. He led, I followed, and on the ground there was this:
It’s a nice boy-sized antiform in the Mather Gorge Formation, a sequence of ancient turbidites that were metamorphosed during Taconian mountain-building in the late Ordovician (~460 Ma). Here, based on the variation in thickness of the layers being folded, I think we’re looking at relict bedding. In other places along the trail, metamorphic foliation is the planar fabric that got folded:
Bonus fold: Here, on the shore of the C&O Canal, is another fold/fault complex with a granite dike and some boudinaged vein quartz, too:
Happy Friday! Enjoy the weekend.